Before I go dredging through microphone positioning, etc, the 2020 is missing one feature that would help a lot with maintaining shot to shot consistency. It doesn't have a headphone connection.
There's just nothing like hearing yourself and being accustomed to hearing and knowing exactly what you sound like in real time
to guarantee high quality. You can't listen to the computer. I don't know if you've experienced this yet or not, but headphone sound in Audacity is One Computer Late. It's the time it takes your voice to go into the computer, into Audacity, turn around and come back out again. It almost always produces an annoying echo or delay.
Yes, Audacity can be managed with ASIO software support. If you know how to compile a computer program, there is provision for you to do that with Audacity. Sometimes that can help with computer delay. Generally, computer programmers are comfortable with this.
This picture was staged, but it's not far from real.
Hang the microphone from a shock mount so it points to your mouth from about nose height. If you scooch the microphone just slightly off center, it leaves space for you to read your script and room to flip pages or do other adjustments without moving your head very much.
A shock mount is recommended.
This is one from one of my microphones in action. The diagonal pieces are expensive rubber bands and if i tap the microphone, it will sit there and vibrate back and forth and slowly come to a stop—silently.
I made one out of hardware store plastic pipes and US Mail rubber bands. It works perfectly well and I used it on several productions. Click on the pictures.http://www.kozco.com/tech/pvcShockMount/shockmount.html
It is also recommended that you use a pop and blast filter. That's the black tennis racket between your lips and the microphone.
It doesn't eliminate P Pops, but it reduces them significantly. You can make one of those at home, too. Panty hose stretched over a pulled out wire coat hanger. Google this. I don't have a favorite. There is another way to do this as well but I don't have any experience with it. It's much smaller, solid (I believe) and it's used closer to the microphone.
Now I'm going to predict the past.
You can't use a pop and blast filter because there isn't room. You need to get really close to your microphone to make the volume and noise sound levels work out. The curse of the non-adjustable microphone without a mixer or interface.
Directional microphones (cardioid pattern) have Proximity Effect. The closer you get to the microphone, the more you sound like an announcer with generous manhood. Unfortunately, the effect changes a lot in the first few inches of mouth distance which I'm betting is where a lot of your shot-to-shot variation is coming from.
I'm a bass. I once briefly played a convincing woman with acting and by using my directional microphone's ability to change timbre with distance. I didn't have to do much, it didn't sound like the regular me at all and the producers kept it in the show.
In My Opinion, you have reached the limit of what you can do with your microphone. If you back away to fit a blast filter in, you will not be able to make volume and noise measurements. There is no such thing as easy quality self-correction because you have no place to plug the headphones.
It's possible there is no good provision to hang it from a shock mount, although I can't tell from the pictures. Your mileage may vary, consult your local listings.
If you have a very good, quiet, well-behaved room, your options are open. Many people are forced to use a certain microphone to make up for their ratty room. You can do whatever you want.